<!DOCTYPE html>
<meta charset="UTF-8">
<title>width composition with interpolate-size: allow-keywords</title>
<link rel="help" href="https://drafts.csswg.org/css-sizing-3/#propdef-width">
<link rel="help" href="https://drafts.csswg.org/css-values-5/#interpolate-size">

<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/css/support/interpolation-testcommon.js"></script>
<style>
:root {
  interpolate-size: allow-keywords;
}
.parent {
  width: 200px;
}
.target {
  width: 100px;
  height: 150px;
}
.target::before {
  display: block;
  content: "";
  width: 100px;
  height: 50px;
}
</style>

<body>
<script>
test_composition({
  property: 'width',
  underlying: '100px',
  addFrom: '100px',
  addTo: 'auto', /* 200px */
}, [
  {at: -0.3, expect: '170px'},
  {at: 0, expect: '200px'},
  {at: 0.5, expect: '250px'},
  {at: 1, expect: '300px'},
  {at: 1.5, expect: '350px'},
]);

test_composition({
  property: 'width',
  underlying: '100px',
  addFrom: 'fit-content', /* 100px, not compatible */
  addTo: 'auto', /* 200px, not compatible */
}, [
  {at: -0.3, expect: '200px'},
  {at: 0, expect: '200px'},
  {at: 0.5, expect: '300px'},
  {at: 1, expect: '300px'},
  {at: 1.5, expect: '300px'},
]);

test_composition({
  property: 'width',
  underlying: 'max-content', /* ignored, not compatible */
  addFrom: '100px',
  addTo: 'auto', /* 200px */
}, [
  {at: -0.3, expect: '70px'},
  {at: 0, expect: '100px'},
  {at: 0.5, expect: '150px'},
  {at: 1, expect: '200px'},
  {at: 1.5, expect: '250px'},
]);
</script>
</body>
